gn: Fix source paths

Change-Id: Idf0c746d7e4e9f03b176744e8ff027be2d5f25ad
Reviewed-on: https://chromium-review.googlesource.com/218520
Reviewed-by: Brett Wilson <brettw@chromium.org>
Reviewed-by: Shannon Woods <shannonwoods@chromium.org>
Commit-Queue: Cem Kocagil <ckocagil@chromium.org>
Tested-by: Cem Kocagil <ckocagil@chromium.org>
diff --git a/BUILD.gn b/BUILD.gn
index ab9568d..7c5a563 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -152,9 +152,9 @@
   shared_library("libGLESv2") {
     sources = rebase_path(gles_gypi.angle_libangle_sources, ".", "src")
     sources += [
-      "libGLESv2/libGLESv2.cpp",
-      "libGLESv2/libGLESv2.def",
-      "libGLESv2/libGLESv2.rc",
+      "src/libGLESv2/libGLESv2.cpp",
+      "src/libGLESv2/libGLESv2.def",
+      "src/libGLESv2/libGLESv2.rc",
     ]
 
     defines = [